Protesters gathered in front of the USDA Rural Development building on Goodfelow Boulevard on Jan. 9 to protest the government shutdown.

Chad Davis | St. Louis Public Radio

The number of cases reported in Missouri this flu season is only a fifth of last year’s, thanks in part to mild temperatures.

There have been 5,460 flu cases reported to the state since early October, according to the Missouri Department of Health and Senior Services. That’s less than one-fifth the number of cases reported during the same period in 2018.

The 2017-2018 flu season was one of the worst in recent memory. In Missouri alone, more than 300 people died from the flu.

Last year’s vaccine did not well match the strain that hit the United States, which was partly why the 2017-2018 season was so deadly, experts say.

But this year’s immunization seems to be more accurate, said Fred Echols, St. Louis County’s director of communicable diseases.

“The vaccine has been a better match this year,” he said. “However, it’s still early in the season. We don’t know how severe the season will be until it’s over.”

The warm weather the region has had through the first months of winter also has likely kept the flu at bay, Echols said. When people spend more time indoors in close contact with others, it increases the chance for flu to spread, he said.

“People are in closed settings for longer periods of time, which increases the probability of a chance that an airborne disease such as influenza can be transmitted,” Echols said. “This year has been very mild.”

Temperatures in the region are expected to drop this weekend and remain in the mid-30s, and there’s a chance of snow. The more winter-like weather could translate into a rising number of flu cases.

Even though the season is halfway over, it’s not too late for people to get a flu vaccine to protect themselves and others who may be immune compromised, Echols said.

“We advise individuals to get the flu vaccine until the end of the season,” he said. “We’re just in week one of the current year, and there’s plenty of time.”

An influenza season can run from October to May, and the flu can flare at different times. Most years, activity peaks from December through March.

The county health department offers free flu shots to county residents who are uninsured at three county-run community health centers across the region, Echols said.